What's on TV Tonight | September 24
How I Met Your Mother 7-7:30pm, CBS. Ted convinces Victoria to leave a note for her ex-fiance (Thomas Lennon) while sleep-deprived Marshall and Lily struggle to keep a secret for Barney.
Partners 7:30-8pm, CBS. Joe's attempt to propose to his girlfriend are complicated by his overbearing business partner and friend.
The Mob Doctor 8-9pm, CBS. Grace is tasked with identifying a mysterious medical condition plaguing the rival of a former mob boss.
Warehouse 13 8-9pm, SYFY. Brother Adrian goes after the agents by sending deadly artifacts to their loved ones.
Castle 9-10pm, CBS. Castle and Beckett put off dealing with their new relationship in order to solve the mystery of who is responsible for her mother's murder.