Tonight's pick of the best telly includes some sobering but fascinating documentaries with 9/11: Life Under Attack and Death on the Common: My Mother's Murder taking centre stage on terrestrial channels.
On-the-ground footage from the Twin Towers attack shows the terrifying reality of being caught up in it, while the now-adult son of Rachel Nickell gives an insight into the crime that claimed his mother which he witnessed as a toddler.
Meanwhile, BBC Two has a new series of A House Through Time, starting with a Victorian era home in Leeds and its remarkable former residents.
Sad times are on the cards for Ferne McCann as she splits with boyfriend Jack in ITV Be's First Time Mum.
And Mortimer & Whitehouse: Gone Fishing continues with a prestigious invite to fish the estate lake at Lincolnshire's Burghley House.
A House Through Time - 9pm - BBC Two
The hit historical documentary series returns with David Olusoga visiting a Victorian house in Leeds to delve into the lives of its past occupants.
In this first episode, he discovers original resident William Bruce was a lawyer who tried and failed to save the life of a man convicted of murder, with other dwellers from the period including Ann Dawson with a rags-to-riches tale and William Nicholson, founder of a Leeds building dynasty that constructed landmarks including County Arcade.
Olusoga revisits the house's social history for three more weekly episodes this series.
9/11: Life Under Attack - 9pm - ITV
It's 20 years on from one of the biggest global events of our lifetime, so unsurprisingly there are many documentaries looking back on that tragic day.
However, this is one of the most poignant - with no narration, it is a simple compilation of first-hand filmed accounts from New Yorkers who saw the attacks on the World Trade Center unfold.
Video footage includes a couple living nearby who are trying to decide whether it's safer to stay in their apartment with their newborn baby or flee the city, and an architect who feels confident that the Twin Towers will not collapse after the planes crash into them.
Of course, anyone who watched the news reports on September 11 will remember the harrowing scenes of smoke, dust and debris engulfing the city streets as the towers fell.
Death on the Common: My Mother's Murder - 10pm - Channel 4
It was one of the most shocking crimes of the 90s, and Rachel Nickell's murder was also the subject of a recent Channel 4 drama, Deceit, which looked into the bungled police investigation that sent the wrong man to prison.
Nickell's two-year-old son Alex was the only witness to the stabbing on Wimbledon Common where his mother was killed, and 30 years on he revisits the scene for this documentary.
Alex will meet the police officers to find out their impressions of him and we'll also hear from his father Andre Hanscombe about how he cared for his son in the aftermath.
Ferne McCann: First Time Mum - 9pm - ITV Be
Ex-Towie star Ferne McCann is used to opening her life up to the cameras and we usually see the funny, touching moments from her life with daughter Sunday in First Time Mum.
However, this week's instalment includes heartbreak as McCann splits from boyfriend Jack and tries to navigate single life again while picking up the pieces as well as parenting Sunday, who is now three.
Mortimer & Whitehouse: Gone Fishing - 10pm - BBC Two
Bob Mortimer and Paul Whitehouse's fishing series is always relaxing viewing, but this week they're in the beautiful surroundings of Lincolnshire's Burghley House where they've been invited to fish the estate's lake.
They might not have much luck in terms of catches, but it's one of their best settings yet as they learn about the 16th century home built by Elizabeth I's lord high chancellor William Cecil.
Watch: Undocumented Ground Zero cleanup workers, the forgotten victims of 9/11