Plot summary
While Angela is serving a customer he begins coughing up blood and dies in the coffee shop. Korsak's name and number are found in his wallet. Maura determines the case of death was warfarin overdose, which the victim had NOT been prescribed, and is also used as rat poison. Investigating why Korsak's number was found in his wallet, they find Korsak's first ex-wife, who gave the name and number to him. Maura takes a cheek swab from Lydia's baby, which she dumped at Maura's, to determine who the baby's father is. Lydia shows up with her brassy mother and reclaims the baby.
Credits
Adapted from Wikipedia contributors, List of Rizzoli & Isles episodes. HTML formatting and reference markers removed.